Antipsychotic Adherence Boosted by Financial Incentives

Ethical concerns apply to the notion of offering money to patients with psychotic disorders to take medication.

Patients with psychotic disorders have better compliance with their depot medication treatments when they receive modest financial incentives for adherence, found a recent study. Even 6 months after the study's conclusion, patients who had received the incentives continued to receive a higher percentage of their prescribed medications than the control group.

“Importantly, 95% of the patients in the intervention group achieved adherence levels of 80% or higher, compared with only 59% of patients in the control group,” reported Ernst L Noordraven, of the Parnassia Psychiatric Institute in The Hague, The Netherlands, and his colleagues in Lancet Psychiatry.

Although their data refuted common concerns about risks of financial incentives, such as unintended increases in substance use problems, medication side effects or negative symptoms, the investigators also addressed the ethical concerns with financial incentives, particularly in patients with greater financial needs.

“There is a risk that if money is offered, the decision of a patient about whether to take medication is not based purely on a balance of risks and benefits of the medication,” the researchers noted. They also acknowledged that providing incentives only in patients with low adherence could disincentivize patients with already better adherence, as well as other ethical concerns they will address in a separate paper.

The researchers conducted a multicenter open-label randomized controlled trial between May 2010 and October 2014 with 169 outpatients, age 18 to 65, at 3 mental healthcare institutions in The Netherlands. The participants had been diagnosed with either schizophrenia or another psychotic disorder and had a prescription or an indication for a prescription for antipsychotic depot drugs.

All of the patients received 12 months of treatment, but 84 were offered $31.64 per month if they received all depot treatments that month. Randomization of the patients was stratified by treatment site, by sex, having or not having a substance-use disorder, and having complied with more or less than 50% of treatments for 4 months before baseline. An overall 92% of patients completed the study with full data available for analysis.

At the start of the study, both groups had a similar Medication Possession Ratio (MPR), the percentage of depot treatments they received out of the total number prescribed. The intervention group had an average 76% MPR compared with 78% in the control group.

After 12 months, the intervention group had an average 93% MPR compared with 77% in the control group — an adjusted difference of 15%. Average MPR for once-weekly depots was 85% in the intervention group and 68% in the control group. Average MPR for once-monthly depots was 97% in the intervention group and 90% in the control group.

“Overall improvement of the MPR in the intervention group was contributed mainly by patients with low adherence rates at baseline (from 52% to 91%), whereas rates in patients with good adherence at baseline remained high after 12 months (around 98%),” the investigators reported. “By contrast, patients in the control group with high adherence rates at baseline (98%) had lower adherence after 12 months (81%).”

During the subsequent 6 months, after the intervention participants were no longer receiving financial incentives, their MPR remained higher, at 83%, than the control group, whose average MPR was 77% — an adjusted difference of 6.5%. More of the intervention group (74%) achieved a consistent MPR of at least 80% than the control group (55%).

No differences in total psychiatric symptoms, positive symptoms, negative symptoms or drug side effects occurred between the groups, nor did differences in hospital admissions, lengths of hospital stay, scores for problematic alcohol and drug use, quality-of-life ratings or psychosocial functioning scores.